According to
James Tait Calder,
George Sinclair, 6th Earl of Caithness, had sometime before his death in 1675 (or 1676) sold his estates to John Campbell, Lord Glenorchy, who was one of his principal creditors. According to
William Anderson, in 1672, debt forced George Sinclair, 6th Earl of Caithness, to resign his titles and estates in favour of Sir John Campbell. Glenorchy married Caithness's widow, the Countess Dowager, who was also a daughter of Campbell,
Earl of Argyll who in turn was a relation of Campbell of Glenorchy. Glenorchy then assumed the title of
Earl of Caithness. However, according to Anderson, Glenorchy took possession of the estates on Sinclair's death in May 1676 and was created Earl of Caithness in June the following year. Glenorchy appointed Sir John Sinclair of Murkle as sheriff and justicary-depute of Caithness, as well as bailie of all the baronies on the Caithness estate, to secure an influential friend in the county. George Sinclair of Keiss, son of Francis Sinclair of Northfield, disputed Glenorchy's right to the title and especially to the lands of
Northfield and Tister, which he had inherited from his father. According to Anderson, George Sinclair of Keiss disputed the claim and seized the land in 1678. The claims of both were submitted to the four most eminent lawyers in
Scotland at the time:
Sir George Mackenzie of Rosehaugh, Sir Robert Sinclair of Longformacus,
Sir George Lockhart, Lord Carnwath and
Sir John Cunningham, 1st Baronet. They decided in favour of Glenorchy and forwarded their decision to King
James VII of Scotland, who then sent a letter to the
Privy Council of Scotland that ordered it to issue a
proclamation prohibiting George Sinclair of Kess from assuming the title of Earl of Caithness. However, Sinclair of Keiss paid no attention to that and not only retained possession of the lands, which he claimed by his own inheritance, but also annoyed Glenorchy's
chamberlains so much that they found it extremely difficult to collect the rents. Almost all of the gentlemen in the county supported the cause of Sinclair of Keiss, in particular David Sinclair of Broynach and William Sinclair of Thura. They gave him all the aid in their power and even helped him to demolish the castle of Thurso East of which Glenorchy had taken possession. The common people were also friendly towards Sinclair of Keiss, and Glenorchy was looked upon as an
usurper who had taken advantage of the necessities of the late Earl and cheated him out of his title and property. The Privy Council passed an
Act on 11 November 1679, charging "haill kin, friends and followers of John, Earl of Caithness, to concuurr and assist" in recovering the lands that were in dispute. ==Battle==